How close are Raimy and Frank to catching the Nightingale? In the Frequency episode airing December 7 titled “Gray Line” more clues emerge.

Here is the synopsis from TV Guide: “Raimy and Frank make a startling discovery about the Nightingale. Meanwhile, Frank’s blindsided by an unexpected betrayal.”

Don’t miss Frequency “Gray Line” airing Wednesday, December 7 at 9/8c on The CW.

Comments? Sound off below.  Or tweet @thenerdygirlexp and @stacyamiller85 .